Electric furnace.



A. HELFENSTEIN.

ELEGTRIO PUBNAGE. APPLIOATION rILBD'jUNE 5, 1912.

Patented Aug. 5, 1913,

Ji -rtl- UNITED smms P T T OFFICE ALOIS HELIENSTEI, or vmnmnusrma-nunaa.

fspeofleation a: Letters mm. i

i Patented Aug. 5,1913.

Application fil ed June 5,1912. Serial Ne. 761392, I

To alt whom it may sondern.-

Be it known that I, ALOS HLFENsTEIm a citizen of Switzer1and,and-aresidentof Vienna, Austria-Hungary, have invented new and usefullmp'ovements in Electric urnmes, of which the following s aspecfication.

endary circuit formed as in the Kjellin heaters of the single windngtype, but as distinguished from these the i'nduced sec-,

ondary is placed outside the metal bath suitably also outside theheater.

tilineal for example. Hereby the heater is made very largely independentof the rest of the transformer elements.

The 'furnace may be constructed as a' tube u accessible throughout, sothat the heating process can be easily overlooked and controlled.'- Inconsequence of the simple straight form of the furnace cold charges 'canbe easily melted down. The furnace chamber is of such dimensions thatheating with fuel, can be efl'ected together with that by induction.These. dimensions, particularly in the case of tubular furnaces, presentthe further advantage th'at the furnacelining is better utilized as bythe im le turning of the tube a fresh length of linng can be introducedas bed' for the bath. For this purpose* the furnace is of courseconstructed so that it will turn, whereby the bath can be movedmechanically during the working without disturbingior moving the otherparts of the transformer arrange ment. I

The stran on the furnace lining in the present heater is uniform, the.furnace lining itself is cooled from outside on all sides by the naturalmovement of the air. The surface of the metal bath, on which ifnecessary purfying additional substances are' caused to act, may belarge, while the depth of the bed should be suitably slight, whereby aquicker and more intense action o the refining substances is eflected. V

In the drawing the invention is illus- The present inventiontconsists'in the sec-.

agim. as employed wasng and nvisibl phase current, Figure 1 beings-transverse section, Fig. 2 ,a longitudinal section .partly in.elevation of a. single-phase-inductio furnace Fig. 3an induction'furnaee'in the secondary ci'cuit ofwhich two lerig hs or; sectmnsjareformed, Eg. 4is v natic .representaton nha trphaseanduc tion furnce, inwhich thi-iee metal bands 'of the diflferenttphases lformlone band,

Fign 5 a' speciallyfayoramearrangement; of; the fixed zseeondary iwinding and %i he primary winding inrelatjon to `the i In 'theembodimentofthe inven-tion here i illustrated thene is provided ;ai .tubnlarconetainer l which is -surrounded by: hearing rings 1' which; aresupported en wing bear ings 1 se !that thetube may .be involved aboutits axis in anyof the well lnum-.nu-`

ners. ,This tube forms the iumaee proper and will. be here-inafterreferred to'as the container. The tube 1 is lined withsuitablenon-.conducting refractory material l and at its ends'isprovided with trunnions 1" having suitable openings therethrough for thepassage of the charge, fuel gases, and the like. One of these trunnionsis located at the charging-end of the furnace and may, where desired; beplaced in communication with a suitable fuel burner 1. The othertrunnion' communicates with a flue 1' in order to provide for the escapeof the waste gases; I i v The whole device is supported over 'a pit 8.provided with suitable walls 9 ,forming the foundation and whereonrests `the bearings 1. Forming a part of the inner wall-of the containerat each end and at such intermediate points as may be found advisable,are conductor rings 10 'provided with flanges 11 which extend annularlyaround the tube 1. In the pit 1 are a plurality of buttresses 12 whereonare' mounted 'the transformer cores 7 around which runs the primarywinding 6 supplied from any suitable source of electricity as, forinstance, the line wires 6'. Extending from end to end beneath thecontainer and between the upper and lower windings 6 isa oopper band 4which'forins the exterior portion of the secondary circuit. At each ofthe flanges 11 this band 'branches Upward as at 4:' and on' theextremity of each of these upturned portions is' provided a pair ofbrushes 4:" which enbrace the respective flange and form elec- 4 tricalconnection therewith'l v The secondary circui-t is completed from one ofthe rings 10 to the other by 'means of the metal bath 3,

'which owing to its high resistanpe becomes intesely heated on passageof the current.

It 'will be noted that while difl`erent arrangements of the transformersand connections are shown in Figs. 2 and 3 and 4 the principle remainsthe same in each case. It is further pointed out that these inductionfurnaces through the employment of a large number of primary coilsfacilitate the regulating of the secondary circut, which is verydifficult with other induction furnaces in the course of working.

Having now particularly described and ascertained the nature of my saidinvention and in what manner the same is to be performed, I declare thatwhat I claim is 1. In a furnace of the kind described; a containerconsisting of a furnace provided with a metal receiving chamber, atransformer core located 'entirely beneath said container, a primarywindin surrounding' said core, and a secondary winding passing adjacentsaid prmary winding and arranged -for connection with the interior ofsaid container, said secondary winding lying wholly beneath saidcontaner.

2. In an electrc furnace; a contaner consisting of a furnace providedwith a metal 'on the 'ends of said secondary winding in contact withsaid flanges.

3. In an electric furnace, a revolubly mounted tubular containerconsisting of a furnace provided with a metal receiving chamber, spacedconductor rings carried by v said container and forming part of theinterior wall thereof, a fiange on each of said rings projectingannularly from the exte'ior of said container, a transformer coreadjacent said container, a primary Winding on said core, a secondarywinding for 'said core, and brushes on the secondary winding andengaging said flanges whereby electrical contact is maintained at alltimes between said secondary wnding and the conductor rings.

In testimony whereof I affix my signature in presence of two witnesses.

ALOIS HELFENSTEIN. Witnesses:

AUGUBT FUGGER, IGNAZ KNORSCHMACHER.

